There isn't really wealth in housing though, not to people that have seemingly profited from house price rises, it's all on paper and irrelevant to people's real day to day lives.
I understand what you are saying, and I pretty much agree, but it's not the fault of people that bought houses when they did that prices have risen and they shouldn't be penalised for it, nor should they be considered greedy.
They didn't know it was going to happen, they didn't ask for it to happen. They just bought houses when it was the right time in their lives, and it's only looking bak that it could be seen to be being the right time economically. But like I say, it doesn't really matter to them. It's not like they have profited in actual real terms. They might have done on paper, but where's the benefit of that when everywhere else is equally as expensive now.
People's wages are better now than they ever were, but it means nothing because the cost of living has gone up so much. It's the same thing.
You are very misguided if you think most landlors have accountants that can fiddle their tax. They don't. You are referring to the super wealthy, not just the regular accidental landlord, or even the regular BTL landlord that is just trying to better their income and provide an asset for their family.
Land value tax would be extremely unfair, would not target those people you want to hit, and it would create less affordable housing while people sold up and stopped providing a rental property for someone who can't afford to buy.